X-rite Europe Gmbh

X-rite Switzerland Gmbh

Heidelberger Druckmaschinen Ag

Gretag-macbeth Ag

Gretagmacbeth, LLC

X-rite Europe Ag

Carl Zeiss Jena Gmbh

WindmÖller & HÖlscher Kg

Peter Ehbets

Beat Frick

Adrian Kohlbrenner

Guido Niederer

Wolfgang Geissler

Adrian Von Orelli

Mark Wegmuller

Frank Schumann

Francis Lamy

Frank Muth

Robert Lange

Bruno Zimmermann

Matthias Scheller Lichtenauer

Manfred Schneider

Werner Huber

Harold R Van Aken

Andreas Ihme

Christopher Riegel

Loris De Vries

Mark Wegmüller

Jorg Hunkemeier

Thomas Senn

Peter Elter

Wilhelm Schebesta

Martin Beyer

Harald Ammeter

David Hasler

Roland Campa

Jörg Hünkemeier

Eckard Vasold

Milos Sormaz

Wilhelm H Kettler

Eckhard Vasold

Wilhelm Kettler

Martin FLASPÖHLER

Frick Beat

Stefan Bornschein

Daniel Fitze

A computer-implemented method for identifying an effect pigment, the method comprising executing, on at least one processor of at least one computer, steps of: a) acquiring sample image data describing a digital image of a layer comprising a sample effect pigment b) determining, based on the sample image data, sparkle point data describing a sample distribution of sparkle points defined by the digital image, wherein the sample distribution is defined in an N-dimensional color space, wherein N is an integer value equal to or larger than 3; c) determining, based on the sparkle point data, sparkle point transformation data describing a transformation of the sample distribution into an (N&#x2212;1)-dimensional color space; d) determining, based on the sparkle point transformation data, sparkle point distribution geometry data describing a geometry of the sample distribution; e) acquiring reference distribution geometry data describing a geometry of a reference distribution of sparkle points in the (N&#x2212;1)-dimensional color space; f) acquiring reference distribution association data describing an association between the reference distribution and an identifier of the reference distribution; g) determining, based on the sparkle point distribution geometry data and the reference distribution geometry data and the reference distribution association data, sample pigment identity data describing an identity of the sample effect pigment.

Apparatus and method for effect pigment identification

A colour measurement device includes a measurement array (MA) which includes: a plurality of illumination arrays () for exposing a measurement spot (MS) on a measurement object (MO) to illumination light in an actual illumination direction () in each case, and a pick-up array () for detecting the measurement light reflected by the measurement spot (MS) in an actual observation direction () and for converting it into preferably spectral reflection factors; and a controller for the illumination arrays and the pick-up array and for processing the electrical signals produced by the pick-up array. The controller is embodied to process the measured reflection factors on the basis of a correction model, such that distortions in the measurement values as compared to nominal illumination and/or observation directions, caused by angular errors in the illumination arrays and/or the pick-up array, are corrected.

Colour measurement method and colour measurement device

A device for radiometrically gauging the surface of a measurement object (O) includes: at least one measurement array featuring an illumination array and a pick-up array; and a processor (P) for controlling the illumination array and the pick-up array and for processing measurement signals produced by the pick-up array and for providing processed image data. The illumination array exposes a region of the measurement object (O) to illumination light at an illumination angle (&#x3b8;) and an illumination aperture angle (&#x3b1;), and the pick-up array captures measurement light, reflected by the measurement object (O), at a pick-up angle (&#x3b8;) and a pick-up aperture angle (&#x3b1;) and guides it onto an image sensor exhibiting a pixel structure. The measurement object (O) is gauged multispectrally in multiple wavelength ranges, wherein the image sensor produces multispectral image data. Angular and spatial conditions are indicated which optimize the measurement device (MD) with regard to characterizing sparkles.

Sparkle measurement

A color measurement device includes a measurement array (MA) which includes: a plurality of illumination arrays () for exposing a measurement spot (MS) on a measurement object (MO) to illumination light in an actual illumination direction () in each case, and a pick-up array () for detecting the measurement light reflected by the measurement spot (MS) in an actual observation direction () and for converting it into preferably spectral reflection factors; and a controller for the illumination arrays and the pick-up array and for processing the electrical signals produced by the pick-up array. The controller is embodied to process the measured reflection factors on the basis of a correction model, such that distortions in the measurement values as compared to nominal illumination and/or observation directions, caused by angular errors in the illumination arrays and/or the pick-up array, are corrected.

A hand-held measurement device for appearance analyses includes a measurement array which comprises a number of illumination means for applying illumination light to a measurement field in at least three illumination directions and a number of pick-up means for capturing the measurement light in at least one observation direction. The illumination directions and the observation directions lie in a common system plane. At least one pick-up means is embodied to spectrally gauge the measurement light in a locally integral way, and at least one imaging pick-up means is embodied to gauge the measurement light in terms of color in a locally resolved way. The spectral pick-up means and the locally resolving pick-up means are arranged such that they receive the measurement light reflected by the measurement field under the same observation conditions and in particular from the same observation direction.

Hand-held measurement device for capturing the visual impression of a measurement object

A hand-held measurement device for appearance analyzes includes a measurement array which comprises a number of illumination means for applying illumination light to a measurement field in at least three illumination directions and a number of pick-up means for capturing the measurement light in at least one observation direction. The illumination directions and the observation directions lie in a common system plane. At least one pick-up means is embodied to spectrally gauge the measurement light in a locally integral way, and at least one imaging pick-up means is embodied to gauge the measurement light in terms of color in a locally resolved way. The spectral pick-up means and the locally resolving pick-up means are arranged such that they receive the measurement light reflected by the measurement field under the same observation conditions and in particular from the same observation direction.

A device for radiometrically gauging the surface of a measurement object (O) includes: at least one measurement array featuring an illumination array and a pick-up array; and a processor (P) for controlling the illumination array and the pick-up array and for processing measurement signals produced by the pick-up array and for providing processed image data. The illumination array exposes a region of the measurement object (O) to illumination light at an illumination angle (&#x3b8;) and an illumination aperture angle (&#x3b1;), and the pick-up array captures measurement light, reflected by the measurement object (O), at a pick-up angle (&#x3b8;) and a pick-up aperture angle (&#x3b1;) and guides it onto an image sensor exhibiting a pixel structure. The measurement object (O) is gauged multispectrally in multiple wavelength ranges, wherein the image sensor produces multispectral image data. Angular and spatial conditions are indicated which optimise the measurement device (MD) with regard to characterising sparkles.

A method for the correction of measurement errors caused by surface effects induced by ink splitting during the color measurement of a printed sheet on a running printing device, includes scanning the printed sheet photoelectrically point by point and forming color and/or density measured values from scanning signals from the scanned points. Those scanned points which have a brightness exceeding a limiting value are identified, and the measured values are corrected by using the identified scanned points. In particular, during the formation of the color and/or density measured values, the scanning signals from the identified scanned points are not taken into account.

Ink splitting correction method

A measuring system for photoelectrically scanning measurement points of a measurement object includes a lighting channel (-) for applying illuminating light to the measurement object (M) disposed in a measurement plane (MP) and a measuring channel (-) for capturing and photoelectrically converting the measurement light reflected by the measurement points of the measurement object M. The lighting channel and/or the measuring channel is configured so as to detect the reflection properties of the measurement points in several wavelength bands. The lighting channel (-) has a spatial light modulator controlled by an electronic control unit () for generating a spatial lighting pattern which causes illuminating light to be selectively applied to measurements points () of interest of the measurement object (M). The control unit () may be equipped with image processing functions and be configured to identify measurement points () suitable for the application purpose from image data of the measurement object (M) and to calculate corresponding lighting patterns for selectively illuminating the measurement points.

Spectral measuring system

Methods for measuring the colour of printed samples by measuring a first spectral proportion of the total spectral reflection factor of a sample by illuminating the sample with light having no UV element are provided. The methods calculate a spectral correction factor by making allowance for the characterisation data of the brightened substrate and the spectral properties of a selected type of illuminating light, adding the spectral correction factor to the first spectral proportion to obtain the total spectral reflection factor of the measured sample. The methods further evaluate the total spectral reflection factor on the basis of measurements taken with illuminating light with no UV element and with UV light only on a limited set of measurement samples, especially on the non-printed substrate only (paper whiteness).

Method of measuring the colour of printed samples containing brighteners

A scanner device includes a color measuring, a support surface for a measured object and a drive unit for moving the measuring head across the support surface and for adjusting the height of the measuring head in a direction perpendicular to the support surface. The measuring head is equipped with an illuminating channel and a collection channel. The illuminating channel has a light source and optical means for illuminating the measured object at a measurement site at a mean angle of incidence of 45&#xb0;. The collection channel has optical means for capturing light emanating from the measured object at the measurement site at a mean collection angle of 0&#xb0; and coupling it into a light guide, which directs the captured light to a wavelength-selective photoelectric transformer, which resolves it into a number of wavelength ranges and generates an electric measurement signal corresponding to each wavelength range.

Color measuring head and scanner device equipped therewith

A scanner device for measuring the color properties of a measured object pixel by pixel has a support surface for the measured object, a color measuring head, a drive unit for moving the color measuring head above the support surface in at least one dimension thereof and for adjusting the height of the color measuring head in the direction perpendicular to the support surface, as well as a measurement and drive control unit which activates the drive unit and co-operates with the color measuring head. It is also equipped with an electronic distance control system which adjusts the distance of the color measuring head above the measurement point in the direction perpendicular to the support surface to a desired measuring distance for every measurement point by means of the drive unit. The electronic distance control system works with measurement values generated by the color measuring head and distance values computed from them. The scanner device is suitable for running high-precision measurements on even the smallest measurement fields without contact and no separate measurement sensor is needed for the distance control system.

Scanner device

Image measurement values of a measurement object, in particular a printed sheet, measured by means of a photoelectric image measuring unit operating on the basis of pixels are corrected with respect to at least one influencing variable which influences the measurement result with a view to at least partially eliminating the effect of this influencing variable on the measuring process. The image measurement values measured by the image measuring unit are converted by correction parameters of a parameter-based correction model into corrected image measurement values which no longer contain the influencing variable affecting the measuring process. The correction parameters used for the parameter-based correction model are automatically calculated using reference measurement values measured at reference measurements points on preferably the same measurement object by means of a reference measuring unit and the image measuring unit. In particular, image measurement values measured without polarization filters are converted into polarization filter image measurement values by means of this method. Influences induced by print medium, fluorescence effects and the influences of non-standard measuring geometries are also corrected.

Method for correcting measured image values

The measuring device comprises a lighting system, a photoelectric receiver unit and optical means. The lighting system applies light to image elements disposed in strip-shaped lighting regions () at a standardized angle of incidence range. The photoelectric receiver unit comprises several photoelectric line sensors () disposed parallel at a distance apart which are sensitized to different wavelength ranges by color filters () connected upstream. The optical means comprise linear optical arrays () which pick up the measurement light reflected by the image elements at a standardized range of angle of reflection and direct it to one of the respective line sensors (). By means of optical screening and other structural features, cross-talk effects between adjacent image elements are largely reduced.

Measurement system and scanning device for the photoelectric measurement of a measurement object pixel by pixel

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Zurich, Switzerland

Peter Ehbets